A dangerous mix of prescription-strength codeine and sugary soda that has been a popular drug in the southern rap community for decades -- and has caused numerous deaths -- could spread to a younger generation through social media, according to a professor of behavioral sciences at the University of Texas.

After a health scare landed multi-platinum rapper Lil' Wayne in a Los Angeles hospital last week and prompted rumors of his death, a spotlight has been placed on the dangerous recreational narcotic drink Wayne and other rappers have sung about.

The concoction has only just started to be referred to as "sizzurp." It is more commonly called "sippin' syrup," "oil," "purple stuff," "drank," "lean" and in one form of the mixture, "mud."

When people on the street want to sell you some, they might ask, "Do you need an oil change?"

"Sippin syrup" is promethazine/codeine syrup mixed with high-caffeine or fruit-flavored soda or alcohol. Fruit-flavored candy is often added to increase its sweetness. According to one expert who has studied its influence in Houston, where the drink originated, "sippin syrup" is "extremely addictive" and remains "very common."

"It is still considered to be the champagne and caviar of drugs here in Houston," said Ronald Peters, an associate professor of behavioral sciences at the University of Texas Health Science Center. Peters has been conducting studies on "sippin' syrup" for 13 years.

Peters said "drank" was first popularized in the 1970s, with Robitussin and codeine. People "would cut it with beer back then," he said, and it was particularly popular in the Third Ward, in Houston's south side.

The next Houston generation grew up with the emergence of hip-hop in the 1990s, and the message of people drinking "sippin syrup" spread like wildfire.

Hip-hop producer Robert Davis, better known by his stage name DJ Screw, created an innovative form of hip-hop music called "Screw music." While others in the southern hip-hop scene were using fast beats, Screw was the first to "slow it down," Peters said, and in his music, "he simply told the world what was going on in Houston."

In one 1996 song by Screw called "Sippin Codeine," his rap opens with the line, "I sip codeine/It makes a south side playa lean."

From Houston, which Peters called the "mecca of hip-hop music in the '90s," "sippin syrup" spread to other states as it gained popularity across southern hip-hop circles. From there, its popularity spread to another new generation that has embraced YouTube, Twitter and other social media.

In the Houston area, people would often drink "sippin syrup" out of Styrofoam cups -- so much so that local law enforcement has picked up people who were spotted holding such a cup while walking down the street.

The Styrofoam cup became a sort of symbol for the drink in the Houston area. Wayne and other rappers have been seen holding large Styrofoam cups in pictures and videos.

But the concoction of promethazine, which is an anti-histamine, codeine, which has opulent properties, mixed with alcohol or caffeine -- the combination of three substances in one -- can be dangerous.

Drinking enough of "sippin syrup" can produce a high very similar to that of heroin, and it can be as addictive.

Peters said not a lot of studies had been done about "sippin syrup." But in one study he conducted in 2003 with around 100 high school-age kids, who said they were current "sippin syrup" users, Peters said many of them reported feeling high after the first time trying it.

"Some of them had issues with insomnia, where they couldn't sleep without it, made them irritable," Peters said. "They reported having 'syrup comas,' you know, that was the extreme."